“You always try to time specific events,” said Patrick Howell, spokesman for Wagner, who handles her social media.

He said he increasingly watches the clock, studying when messages have the most impact, keeping in mind that Washington is an hour ahead of Missouri.

The rise of social media means that conventional wisdom can be shaped within hours. Politicians have a limited amount of time to make their mark in a constant echo chamber — or be left out of the debate.

Behind the scenes, Missouri officials have quietly honed their strategies on Facebook and Twitter, venues where they can bypass traditional media, raise their public image and have a direct conversation with constituents.

They have adopted varying strategies based on message, timing and personality. Some now even fund studies to measure social media metrics.

Wagner, R-Ballwin, doesn’t tweet or post on Facebook herself, Howell said, but she personally directs the content and conversation.

“One year ago, the world lost a beacon of freedom and democracy to those that had no voice,” it said. “Here’s to the #IronLady.”

U.S. Sen. Claire McCaskill takes a different approach. Her tweets are done without the approval or help of campaign aides — something that can cause some heart-stopping moments for staffers.

“We see the tweets at the same time the rest of the world does, with no warning they’re coming,” said John LaBombard, a McCaskill spokesman. “That said, the authenticity of Claire’s tweets is exactly what makes it an effective communication tool for her and her constituents.”

In 2011, she announced on Twitter that she was “tired of looking and feeling fat.” Several months later, McCaskill declared that she had lost 50 pounds because the public announcement had kept her accountable.

Such a policy has drawbacks, the chief one being that a busy politician can’t keep a feed routinely updated. In McCaskill’s case, her staff operates its own Twitter feed for updates from their office.

In St. Louis, the dominant political voice on social media is Mayor Francis Slay, who has evolved his strategy on various Web platforms in recent years.

“Successful Twitter feeds speak in the voice of the politician,” Callow said. “The mayor’s is successful because it sounds just like the mayor. If Claire were to sound like the mayor, I suspect that people would be puzzled. Possibly alarmed.”

Slay’s nonstop campaign operation issues tweets with his account, particularly focused on the nuts and bolts of the city: snow removal, storm damage, street repairs and other announcements. Slay has encouraged the city’s department heads to use Twitter as a communication tool.

“It has become contagious in his administration,” Callow said.

Callow, like Wagner’s staff, also recognizes the importance of timing. He said Slay’s campaign funded a study analyzing the mayor’s Facebook account, looking for the best time to post various messages based on interaction with users. He declined to provide the results.

Slay recently gave a face-lift to his website so it doesn’t mimic content already on his Facebook or Twitter account. But Twitter remains his most frequently updated venue. On Monday, Slay used his initials on seven tweets.

“Unlike many mayors, he has had the benefit of being able to speak to Jack Dorsey,” Callow said, noting that Dorsey, Twitter’s co-founder, grew up in the city.

But the frequent tweets have caused some to infer that Callow is the real author.

Or, Callow said, “After 13 years of association, we likely sound like each other.”